Hog knife



Jan. 15 1924.

E. F. HOWARTH Fatented den. 15, 1924.

NETE SATS @lTlil.

EVERETT ll. HOWABTI-I, OF FITCHBURG, TKASSACHUSET'IS, ASSIGNOR,'BY DEESNE AS- SIGrNlvIENTS, TO SIMONDS SAJV AND STEEL COIJI PANY, OE FITCHBUBG, MASSA- CHUSETTS, A. CORPORATION OF MASSACHUSETTS.

HOG KNIFE.

Application fiIed July 27, 1922. Serial No. 577,827.

T0 or whom it may concern Be it known that l, EVERETT F. HowAu'rrI, a citizen of the United. States of America, and resident of Fitchburg, in the county of Worcester and State of Massachusetts, have invented new and useful Improvements in Hog Knives, of which the following is a specification.

This invention relates to cutting instruments of the type known as hog knives having one or more slots disposed perpendicir larly to the cutting edges thereof to adapt the knives to be adjustably mounted in holders or machines such as are used for cutting up wood pulp, for cutting up rags, for planing wood surfaces, etc.

The object of the present invention is to provide a knife of the class described which has improved means for retaining it in adjusted position, which is more efficient and satisfactory in operation, and which can be more economically and rapidly produced.

In order to illustrate the invention, one concrete embodiment thereof is shown in the accompanying drawings in which:

Fig. 1 is a perspective view of a knife;

Fig. 2 is a sectional view on the line 2-2 of Fig. 1; and

Fig. 3 is a side elevational view, partly in section and partly broken away, showing the knife mounted in a rotary holder.

The embodiment of the invention shown for the purpose of illustration comprises a knife a, substantially rectangular in form, having one side beveled to form a cutting edge 0 and the opposite edge recessed to form slots 6 for attachment to a holder. While the knife may be used in various forms of holders depending upon the purpose for which it is used. the holder shown in Fig. 3 will serve as an illustration, This holder comprises a rotary head it fast on a shaft 2' and provided with one or more recesses j against one side of which each knife is clamped by bolts k, nuts 6 and washers 9.

According to the preent invention the side of the knife engaged by the washers g is serrated adjacent the slots 6 to prevent slippage of'the knife relatively to the holder when taking a heavy out. These serrations are forced up from the outer surface of the knife in the form of sharp ridges adapted to bite into the washers which constitute a part of the holder. The ridges may be made with a chisel as illustrated in Fig. 2, the chisel being operated either by hand or preferably in a suitable power machine. Theserrations eX- tend above the surface of the knife so as to bite into the washer even though, the washer overlaps the unserrated portion of the knife. The ridges preferably incline away from. the cutting edge of the blade so as more effective ly to bite into the washer when taking a heavy cut. This inclination may readily be obtained by inclining the chisel away from the cutting edge in forcing up the ridges.

Inasmuch as knives for different purposes are beveled on different sides the knives illustrated in Figs. 1 and 2 are shown as beveled on the outside while the knife in Fig. 3 is shown as beveled on the inside.

W hat I claim is:

l. A tool of the class described comprising a. substantially flat plate beveled at one edge to form a cutting element and having a. recess extending inwardly from. its opposite edge to accommodate a bolt for securing it to a holder, and a series of ribs project ing upwardly from the surface of the plate at either side of the recess, said ribs inclining away from the cutting edge of the plate and having sharp edges extending substantially parallel to said cutting edge.

2. A tool of the class described compris ing a substantially flat plate beveled at one edge to form a cutting element and havingarecess extending inwardly from its opposite edge to accommodate: a bolt for securing it to a holder and a series of ribs projecting upwardly from the surface of the plate at either side of the recess, said ribs inclining away from the cutting edge of the plate and having sharp edges extending substanti ally parallel to said cutting edge and being restricted to a part only of said surface adjacent said recess.

Signed by me at Fitchburg, Mass, this 22nd day of July, 1922.

EVERETT F. HOWARTH. 

